The use of single nucleotide polymorphisms (SNPs) is likely to become a major tool for the discovery of genetic linkage and disease association in the coming decade. New technologies currently entering the laboratory will allow investigators to perform high throughput studies that, until now, were impossible. The Genotyping Core proposes to locate SNPs in genes with demonstrated or presumed relevance to human cardiopulmonary disease. We will select 20 candidate genes for SNP analysis per year in airway diseases (cystic fibrosis, chronic obstructive pulmonary disease, and asthma) and selected from comparisons of our expression profiling analysis in human and animal models of human disease. We anticipate three to five SNPs per gene, which we can then evaluate in well-defined patient populations. We hypothesize SNP may explain phenotypic differences in carefully defined disease severity.